Please help with my 4-panel Certainteed sliding doors

A quick learner from New Jersey says:

My living room has a 4-panel set of Certainteed sliding doors (Newcastle XT).

The two middle panels move, and the two side panels are stationary. The two sliding panels lock in two ways:

1) mortise locks: These locks are doing fine. The left-hand sliding panel is equipped with three mortise locks, the tongues of which lock into "keepers" on the right-hand-sliding panel.

2) the right-hand panel has its own collection of three locks, but they don't latch onto the left-hand door; these locks are hidden behind a hard plastic column the height of the entire panel, which has the keepers for the left panel attached to it as well. I detached this plastic column from the right-hand panel so you could see what I mean.

Opening and closing the right-panel locks does not cause latches to pop out, as it does with the left-panel locks; with these locks, articulating the lock handle just causes the circular protrusions at the top and bottom of the lock to move up and down. My best guess is that the reason for this is because the right panel's locking mechanism is to extend metal cylinders into the header and footer of the door, where these cylinders fit into brackets affixed to the top and bottom tracks for this purpose. The three locks on the right-hand panel seem to "communicate" with one another via these long metal pieces.

These long metal pieces have holes corresponding to the small protrusions on each lock, and the protrusions move up and down as you lock or unlock the locks. In short, when you turn the handle on the central lock, that moves that lock's small circular protrusions up or down, which moves the long metal pieces up or down, which then moves the upper and lower locks to either insert or withdraw the metal cylinders from their housings in the header and footer.

And now we finally come to the problem: The central lock of this right-hand panel is somehow broken, so that articulating the locking handle no longer raises and lowers the circular protrusions. The result is that this sliding panel is stuck in the locked position, with a metal cylinder stuck in the extended position in the footer.

What lock do I need to buy in order to replace the central lock of the right-hand panel?

Thank you --

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Casey from SWISCO responded:


Though we have seen the extended version of the 82-238 mortise lock that takes up the length of the door in the past, your door setup leads us to believe that this is some kind of custom job since the doors are using more than one style of mortise lock. Unfortunately, we do not carry a version of this lock that uses locking posts on the top and bottom that you pointed out, or the extended version used by the other sliding door panel.

With that being said, I suspect that your smaller mortise may be damaged and is missing the faceplate and locking hooks. See our photo below that shows the 82-238 mortise without the faceplate, which doesn't look dissimilar to your photo. I also see installation holes on the top and bottom of the mortise cutout in the door that could be used to attach the faceplate.

If my suspicions are correct, there is a chance that you could use the 82-238 in your door and attach the 89-030 in the doorframe to correct the problem. We can't make any guarantees since there is no undamaged assembly to compare but these would be our best replacement options for your door. Take a look and see what you think.

Alternate view of 82-238
Alternate view of 82-238

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